The flange/turbine outlet is 2.5". The 3" pipe will fit if I hammer in the edges for bolt clearance, but I'm worried about flow. I assume a smooth transition would be better, but I'd like to know what everyone else is doing.

EDIT: Some pics. The one with the red circle shows how the downpipe aligns with the flange. Basically one side is flush and the other side bears the full 0.5" difference.








Modified by Legion at 12:56 AM 2/22/2008


Modified by Legion at 1:01 AM 2/22/2008

 

what my current 240 setup is
5bolt flange pipe coming out >vband>3'dp

 

just center it up better and weld that **** on there! i had my downpipe just like that, grap your bolts and find the best spot to weld it.

 

I myself would get a 3 inch flange from atpturbo.com , or use a transition.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AaronJ &raquo;</TD></TR><TR><TD CLASS="quote">just center it up better and weld that **** on there! i had my downpipe just like that, grap your bolts and find the best spot to weld it.</TD></TR></TABLE>

That's the best it can be centered. It doesn't look that way, but I spent literally 2 hours mocking/taping it into that position before tacking it.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RCautoworks &raquo;</TD></TR><TR><TD CLASS="quote">I myself would get a 3 inch flange from atpturbo.com , or use a transition. </TD></TR></TABLE>

Well the flange opening is the same size as the turbine outlet, so a 3" flange wouldn't help.

I'm curious about the flow characteristics. I don't know if there are any ME's with knowledge in fluid dynamics around here... I'm thinking that the best course of action would be to make the outer turn of the radius flush with the flange opening so that the exhaust gases don't lose velocity. That way the inner edge of the radius would just be a low-pressure zone.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Legion &raquo;</TD></TR><TR><TD CLASS="quote">

That's the best it can be centered. It doesn't look that way, but I spent literally 2 hours mocking/taping it into that position before tacking it.

Well the flange opening is the same size as the turbine outlet, so a 3" flange wouldn't help.

I'm curious about the flow characteristics. I don't know if there are any ME's with knowledge in fluid dynamics around here... I'm thinking that the best course of action would be to make the outer turn of the radius flush with the flange opening so that the exhaust gases don't lose velocity. That way the inner edge of the radius would just be a low-pressure zone.</TD></TR></TABLE>

theres really not much you can do with the bolted flanges. maybe weld a Vband to your housing?

 

http://store.racing-solutions.....html

I bought one of those. Just cut some of the long unflared part off slide it into the flange and weld.

 

Quit worrying about flow. It's not worth your time unless you are trying to build something very competitive. Just weld it up and run it.

If you want to be ridiculous about it and make DP clearance twice as hard:

http://www.acestainless.com/in...Id=45
http://cgi.ebay.com/ebaymotors...ZWDVW

or go to Autozone/Pepboys/NAPA/whatever and buy a $5.00 steel reducer.

 

Eh, **** it. I just welded it as is.